Method of making knives.



A. M. ALEXANDER.

METHOD OF MAKING KNIVES.

APPLICATION FILED JAN. 7, 1910.

1,003,409. Patented Sept. 19,1911.

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ALEXANDER :nz erszramnns, or BEVERLY;MASSACHUSETTS, ASSIGNOR TO UNITEDsoon rsscnrnnnr Q'QMPANY, or rerun-son, JERSEY, A CORPORATION or NEWJERSEY.

Speoiflca tion of Letters Patent.

METHDD Uh MAKING KNIVES.

fti atcnt ed Sept. 19, 1911..

Ilqmlieatien filed January F, 1310. Serial No. 536,835.

To cZZ whom may concern.

Be it known that l, ALEXANDER M. ALEX- lanolin, a citizen of the UnitedStates-1 siding, at Beverly., in the county of Essex and State of illussachusetts, have invented. certain isuprovements lllethods ot' Making;Knives, of which the following description. in nncc.'ion with theaccompanying drawings, is a specification, like reference characters onthe drawings indicating like parts in the figures.

This invention relates to a method of making cylindrical knives. 'lhescknives which have the cutting edge formed upon one end of a cylinder areused in various arts. the illustrated knife, which the method hereindescribed is especially intended to produce, being employed in a machinefor skiving the parts of boot and shoe uppers such as shown in myco-pcndintr application. Sci. No. 522,905, filed October 16,

Cylindrical knives have long been employed in skiving niachii'ies, butowing to the great cost of the knives these machines have not come intovery extensive use. There are, however, some advantages in skiving witha cylindrical knife which make skiving machines employing such knivesdesirable in the n'lanutacture of boots and shoes, and in ordertherefore that these advantages may be generally availed of without theaccompanyii'u excessive cost of the ski'viug knives an object oi? thisinvention is a method 0t making cylindrical knives, especially adopt--ed for use in skiving' machines, by Which. these knives may be producedat a low cost.

To this end the method contemplates the novel procedure hereinafter setforth by which a knife having a true cylindrical form, which is ot a totit accurately the holder for which it is made which is properlyl'uu'dcncd and tempered may be easily and quickly produced.

Where accuracy of form and fit has been especially desirable, as inskiving machines cylit'idrical,knives have usually been madel'un'etoforc by forging a blank and then mil in; the blade out of theblank. Knives thus produced are obvii'iusly comparatively expensive. llythe method of this invention a band oi st el oi. the proper compositionand length is first rolled into the desired cylindrical form is thenconfined in a holder constructed to maintain this'form and .Whileconfined in tl'lis holdcr is hardened throughout that portion. which,upon successive grindings, will furnish. the successive cutting edges.

In Figure l of the accompanying drawings sl'iown a knife of the typeintended to be produced by this method; in Fig. 2 is shown the holder inwhich the knife is confined for the hardening operation after ithas'becn rolled into its shape, the holder in this figure. being shownwith the parts in the relative positions into which they are put whenthe part of the knife to be hardened. is to be immersed in the heatinghath; 3 is :1 section through the knii'c holder showing the parts in therelati *0 position into which they are put when the knife is to beimmersed in the inn-cloning bath.

The knife shown in .lfiigi l is fi'n'med of a ribbon or band ofstccl ofsuitable coniposition, the band being preferably of uniform compositionthroughout. This band having been cut to the proper length is firstrolled by any suitable rolling machine into the desired cylindrical formprovision being made in measuring the original length for a slightcontraction inv hardening and temperin The band of steel is preferablyrolled into its cylindrical form While in its unteinpered condition.Having been rolled into cylindrical form, the knife is placed in heholder shown in Figs. 2 and. 3, this holder being adapted to engage theknife both on its outside and on its inside surfaces, as shownespecially in Fig. 3. The holder comprises a rin 4 having an annularsockbt (i which. receives the knife 2 and in which the knife is confinedby a second ring 8 milled to fit within the knife 2 when it is in thesocket l and to rest upon the bottom of said socket. The ring 8 is ofsuch Vertical dimension that its upper surface lies flush with the uppersurface of the rin 4- Whcn it in the socket 6. A bail 10 having carswhich receive trunnions 12 upon the ring 4 is used by the operator tosupport and lift the ring during the heating and hardening operations.The ring; 4 is also provided With an eye piece 14 so located that theoperator may engage it with a hook and turn the ring over after theheating operation to cause the ring" to assume the position shown inFig. 3 for the hurdcnin operation.

The method of procedure inthe heating and hardening operations is asfollows:.

The parts being in the position shown in its exposed portion is heatedto the desired, hardening temperature, the portions of the knifeimmediately adjacent to the exposed portion being heated by conductionthrough the rings 4E and 8. After the knife is heated to the desiredhardening temperature, the holder is taken from the heating bath and theoperator engages the eye 14 With a hook or other tool and turns theholder into the position shown in Fig.3. The holder and knife-are thenimmersed in the hardening bath which is preferably an oil bath. It Willbe seen that the holder strikes the hardeningbath first and that thusthe confined portion of the knife is first cooled and that theunconfined portion is cooled gradually, the part of.the exposed portionof the knife nearest the confined portion being first cooled and thenthe succeeding parts until the outer edge of the unconfined portion isreached. This procedure keeps the knife from assuming a cannon mouthform. After the knife has been heated and hardened in the" mannerdescribed it is removed from the holder and put into a tempering bathand the hardness drawn to the required degree.

Having described my invention, What I claim as new and desire to secureby Letters Patent of the United States is 1. That improvement in the artof making cylindrical knives which consists-in rolling into the desiredcylindrical form a band of steel of the proper composition and length,confining a marginal portion of the blank thus formed in a holderconstructed to main tain the cylindrical form of the blank, immersingthe unconfined portion only of the blank in a heating bath, and thenreversing the holder to bring the unconfined portion of the blank abovethe holder and immersing the holder and blank in a hardening bath.

2. That improvement in the art of making cylindrical knives whichconsists in rollin into the desired cylindrical form a band or steel ofthe proper composition and length, confining a marginal portion of thecylindrical blank thus formed in a holder constructed to maintain thecylindrical form, immersing the unconfined portion of the blank in alead heating bath and then immersing the holder and blank in a hardeningbath in such manner that the confined portion of the blank is firstcooled and that the unconfined portions which are heated to highertemperatures are cooled successively toward the edge which is to formthe cutting edge.

In testimony whereof I have signed. my name to this specification in thepresence of two subscribin witnesses.

ALEXAfiDER M. ALEXANDER.

Witnesses:

LEONARD M. J OHNSON, H. DORSEY SPENCER.

